Data String
If A (asynchronous mode) is specified in position 5 of the calling data structure and the function is completed successfully, the following data string is returned:
| Byte | Definition |
| 1 | A 1-character presentation space short-name (PSID) |
| 2-8 | Reserved |
| 9-12 | 4-byte binary value in which the event object handle is returned by EHLLAPI. The application can wait for this event object. |
If M (asynchronous message mode) is specified in position 5 of the calling data structure and the function is completed successfully, the following data string is returned:
| Byte | Definition |
| 1 | A 1-character presentation space short-name (PSID) |
| 2-8 | Reserved |
| 9-10 | Task ID of asynchronous message mode |
When the session connects or disconnects an application window receives a message. The message is the return value of RegisterWindow Message (PCSHLL). The wParam contains the Task ID returned by the function call. HIWORD of lParam contains a 21 if the session is connected to the host or a 22 if the session is disconnected. The LOWORD of lParam contains the function number 80.